I made a bell/wind chime that chimes the A-note (like the beginning of the ACDC song "Hell's Bells"). It hangs on the wall and when the wind blows it bangs the clapper, the hanging cylindrical piece of steel, into the bell, which is the hanging slab of steel. It took some finessing but it worked out really well.
Step 1: Cut Some Steel
So that photo is actually of what was left AFTER I cut off what I needed, and I don't know why I bent it like that except I already had the torch out and felt like having fun I guess. But yeah, I torch cut a piece of 9" wide x 3/8" thick steel plate and then I ground the edges straight on a disk sander.
Step 2: Hang Up the "bell"
In order to keep the vibration going and be able to really hear it's true notes, I had to get it off of the ground. So I drilled a hole in the top and hung it from a gantry to work on. So the whole piece was made while it was hanging.
Step 3: Make the "clapper"
For this, I chose a 1 1/4" diameter solid steel rod. I needed it to be nice and heavy so that it would keep up some momentum. I think I cut it with an abrasive chop saw, or maybe a horizontal band saw. I cannot remember. But then I used the milling machine to drill a hole through the side of it so that I could attach the wire rope to hang it from.
Step 4: Start Adjusting the Length of the "bell" and the Placement of the "clapper"
Basically this is just trial and error. I used a tuning app on my phone and banged on the bell with the clapper at various heights, grinding off a few 1000's of an inch from the bell until it was an A note. I moved it to my studio from this other shop so I could work on it more, and used my little engine crane to hang it.
Step 5: Making the Wall Mount/ the Right Hanging Hardware
I had to make sure that the bell hung far enough from the wall that it could spin around 360 degrees and not hit the wall. So I used the torch to heat bend some of the 9" wide steel plate into a 90 degree angle. I have pictures of it finished, but none in process because it was pretty crazy. We had to use two torches, one on either side of the material, and a hole bunch of leverage. Didn't have a free hand for documentation at the time. Then I wanted to used these machine screws that required a counter-bored hole so I put it on the mill and drilled and counterbored the holes.
Then I got all the right hardware. A big wire rope. Cast iron wire nuts. Some big industrial cast eye-hooks. Once I had the hardware al figured out, I got some anchors because this is a 150 pound bell. The gallery had hollow drywall+plywood walls, so I used toggle bolts.
The gallery painted the walls green, not me.
Step 6: FINISHED- HELL'S BELL
It works. It bangs the A-note slowly in the breeze and sounds like the first few seconds of "Hell's Bells".